小编Aar*_*ron的帖子

这是一段代码作为一个例子,其余的只是方法(看迷宫类的底部).所以当这个实例化时,使用

Maze labyrinth = new Maze();

和

System.out.println (labyrinth);

这将打印出网格数组.这是合法的吗？我认为所有类都需要构造函数如何打印出二维网格数组？

迷宫课程:

public class Maze
{
    private final int TRIED = 3;
    private final int PATH = 7;
    private int[][] grid = { {1,1,1,0,1,1,0,0,0,1,1,1,1},
                             {1,0,1,1,1,0,1,1,1,1,0,0,1},
                             {0,0,0,0,1,0,1,0,1,0,1,0,0},
                             {1,1,1,0,1,1,1,0,1,0,1,1,1},
                             {1,0,1,0,0,0,0,1,1,1,0,0,1},
                             {1,0,1,1,1,1,1,1,0,1,1,1,1},
                             {1,0,0,0,0,0,0,0,0,0,0,0,0},
                             {1,1,1,1,1,1,1,1,1,1,1,1,1} };

    public String toString ()
    {
        String result = "\n";
        for (int row = 0; row < grid.length; row++)
        {
            for (int column=0; column < grid[row].length; column++)
            result += grid[row][column] + "";
            result += "\n";
        }
        return result;
    }

}

在我的驱动程序中,这行给了我cannot find symbol错误,我不知道为什么.该方法在SavingsAccount类中明确定义,我可以参考我的驱动程序中的所有其他方法但不是那个,我尝试将类型更改为double,等等但仍然无法正常工作.

Account acct2 = new SavingsAccount (name);
acct2.calculateBalance();

SavingsAccountclass继承自Account类:

public class SavingsAccount extends Account
{
    private final short minBalance = 0;
    private double overdraftFee;
    private double yearlyInterestRate = 0.02;
    private double interestAmount;

    public SavingsAccount (String name)
    {
        super(name);
    }

    public double withdraw (double amount)
    {
        if (accountBalance - amount >= minBalance)
        {
            accountBalance -= amount;
            System.out.print ("Withdraw Successful");
        }
        else 
        {
            accountBalance -= amount;
            overdraftFee = accountBalance * (0.10); …

我正在尝试从Car的父类中获取一个参数并将其添加到我的数组(carsParked)中,我该怎么做？

家长班

public class Car
{
    protected String regNo;       //Car registration number
    protected String owner;       //Name of the owner
    protected String carColor;

    /** Creates a Car object
     * @param rNo - registration number
     * @param own - name of the owner
     **/
    public Car (String rNo, String own, String carColour)
    {
        regNo = rNo;
        owner = own;
        carColor = carColour;
    }

    /** @return The car registration number
     **/
    public String getRegNo()
    {
        return regNo;
    }

    /** @return A …